ifty years ago today, news from Moscow swept around the world - the Soviet Union had launched a man into space and brought him safely back to Earth.

The world's first space flight by cosmonaut Yuri Gagarin on April 12 1961 lasted only 108 minutes, but its impact on space exploration and the Soviet and Russian people will never be forgotten.

Gagarin blasted off from Kazakhstan and into history with two simple words: "Let's go."

Those who trained with him are still in awe of what the Soviet fighter pilot achieved.

Boris Volynov was one of the original cosmonauts selected with Gagarin in the embryonic Soviet space program.

"How can one not be proud of him when the whole of humanity was proud of him," he said.

"American astronauts have repeatedly stated it was Yuri Gagarin who called them to space, and that is true."

Days after the flight, when Gagarin arrived in Moscow, the politburo was there to greet him. His breakthrough mission came during the height of the Cold War, in the middle of the furious space race between the Soviet Union and the US.

The space flight sparked wild celebrations all over the USSR and even now, for people like historian Natalya Lebedeva, the memories of that time are crystal clear.

"The day of Gagarin's flight, that is probably one of the happiest days of my life, because of the accumulation of happiness that gripped you," she said.

"Happy moments usually last for several minutes. Euphoria of happiness. But this was a much longer and much deeper feeling of happiness."

Almost instantly, Gagarin became a national hero, his flight a symbol of Soviet achievement.

Newspapers called it a great victory for "our regime, our science, our technology, our courage".

Looking back, the flight is often seen as the peak for the Soviets in space.

Gagarin himself was killed in a flight training accident only seven years later and hopes a Russian would reach the moon were never realised.

And even though Russian rockets continue to carry people into space, for program veterans such as Vladimir Poroshkov, who spent 30 years working at the launch centre in Baikonur, the magic is gone.

"Everything goes routinely, like train and aeroplane movements. There are so many cosmonauts now that one doesn't remember them all," he laments.

He says he does remember a lesson from the space race - one that took decades to sink in. The Soviet Union and America both could have gone farther, faster, if they had worked together in the first place.

"If we had worked with the Americans from the very start and gained space together we would have progressed long ago," he said.

"But since it was secrecy on both sides, each spent its own money, and that is not endless."

A week before this anniversary, a rocket blasted off from Kazakhstan carrying an American and two Russians to the international space station, following in the footsteps of Yuri Gagarin half a century later.